But what made the OSR happen in the first place... where did the impetus for an old school renaissance come from?

For me, it's one simple thing - realizing that my gaming present just wasn't as awesome as my gaming past.

Now, some might point to nostalgia or role-colored glasses. Perhaps I'm only seeing the good things in the past and putting them on a pedestal. Sure, there may be some of that, but I can assure you, I wasn't thinking about quitting roleplaying altogether in the 80's and early 90's. Yet, that's almost what I did back in 2011.

Having got that out of the way, the vast majority of OSR gamers probably wondered, is it me? Did I change or was there something about the rules, system, approach to running games that changed?

In 2012, after hearing about the OSR and invigorated by some new old school-ish RPG called Dungeon Crawl Classics, I hoped that it wasn't just me, that I was pretty much the same guy, but mainstream gaming had gone in a different direction and we were no longer sympatico.

Sure enough, that was it. I realized that the old ways were better (from my point of view), and stopped playing RPGs like D&D 4th edition in favor of a melting pot of B/X, DCC, S&W, and AD&D. Then going back to other games from that time period like Call of Cthulhu, Paranoia, Vampire: the Masquerade, and others.

From there, I began developing my own old school D&D content and then my own RPGs with a decidedly old school feel.

When it came down to it, that's why the OSR became a thing. Enough of us reached a point where decades old gaming was noticeably more awesome than gaming now.